title: The increased expression of proteins involved in proliferation, DNA repair and DNA methylation in spleen of mice exposed to E. coli O157:H7 lipopolysaccharide.
abstract: Previous research showed that the consumption of heat-killed E. coli O157:H7 bacteria resulted in an increase in the level of DNA damage in intestine, liver and spleen cells. We hypothesized that certain bacterial components released from heat-killed bacteria trigger this response. We analysed the possibility that bacterial components [such as lipopolysaccharides (LPS)] could induce changes in the level of proteins involved in cell proliferation, DNA repair and DNA methylation in distal spleen tissues of mice. Four-week-old male mice were provided water supplemented with whole heat-killed E. coli O157:H7 bacteria or components of bacteria (DNA, RNA, proteins and LPS). Spleen cells responded to exposure to whole heat-killed bacteria and LPS with an alteration in the level of PCNA proteins, DNA methylation proteins (DNMT1, DNMT3A, DNMT3B, and MeCP2) and DNA repair proteins (APE1 and KU70). Other bacterial components analysed in this study mostly did not alter protein expression. The data suggest that LPS is a bacterial component capable of inducing molecular changes in naïve spleen cells of hosts exposed to it.
authors.affiliation: Department of Biological Sciences, University of Lethbridge, 4401 University Drive, Lethbridge, T1K 3M4, Canada. igor.kovalchuk@uleth.ca
authors.forename: Igor
authors.initials: I
authors.lastname: Kovalchuk
authors.forename: Paul
authors.initials: P
authors.lastname: Walz
authors.forename: James
authors.initials: J
authors.lastname: Thomas
authors.forename: Olga
authors.initials: O
authors.lastname: Kovalchuk
mesh_terms: D000818:Animals; D034961:Antigens, Nuclear / Q000378:metabolism; D049109:Cell Proliferation; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000378:metabolism; D004249:DNA Damage; D019175:DNA Methylation; D000090205:DNA Methyltransferase 3A; D004260:DNA Repair; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D019453:Escherichia coli O157; D029968:Escherichia coli Proteins / Q000633:toxicity; D000072200:Ku Autoantigen; D008070:Lipopolysaccharides / Q000378:metabolism / Q000633:toxicity*; D008297:Male; D051783:Methyl-CpG-Binding Protein 2 / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D013154:Spleen / Q000378:metabolism / Q000382:microbiology; D000097584:DNA Methyltransferase 3B
chemical_list: D034961:Antigens, Nuclear; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases; D000090205:DNA Methyltransferase 3A; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D000072200:Ku Autoantigen; D008070:Lipopolysaccharides; D051783:Methyl-CpG-Binding Protein 2; D018809:Proliferating Cell Nuclear Antigen; D000097584:DNA Methyltransferase 3B; C000715535:Dnmt3a protein, mouse; C497393:Mecp2 protein, mouse; C000619381:Dnmt1 protein, mouse; C000606510:Xrcc6 protein, mouse; C486216:Apex1 protein, mouse
keywords: DNA damage and repair; DNMT enzymes; Mus musculus; PCNA and cell proliferation; lipopolysaccharides; spleen cells